A field-programmable gate array (FPGA) is an integrated circuit that is capable of being reprogrammed in the field after manufacture. In particular, an FPGA is made up of logic gates whose connections are readily programmed into specific configurations by the user. The design, which is resident in the FPGA, is proprietary information that can be very valuable. Accordingly, the ability to keep others from obtaining the programming information is important for both business and military reasons. Typical non-volatile FPGAs come with a test mode and a read back mode. Bedsides their intended functions, these modes enable reverse engineering of the FPGA device.
Some manufactures of non-volatile FPGAs protect important or sensitive information in the FPGA by disabling the test and read back modes with the use of security bits. However, the use of thermal imaging can be used to locate these security bits. Once located, they can be disabled with a high energy light source. In addition, other proprietary information that is stored in memory devices in communication with associated FPGAs can be obtained by reverse engineering techniques.
For the reasons stated above and for other reasons stated below which will become apparent to those skilled in the art upon reading and understanding the present specification, there is a need in the art for a tamper response system that protects proprietary information from reverse engineering techniques.